What is Core Theme 5 in WJEC GCSE Geography?

Core Theme 5, Weather, Climate and Ecosystems, is the first core theme of Unit 2 (Environmental and Development Issues), a 1-hour 30-minute written exam worth 35 percent of the GCSE. It covers climate change during the Quaternary, weather patterns and processes including UK weather and tropical storms, the processes and interactions within ecosystems, and human activity and the sustainable management of ecosystems such as the tropical rainforest.

What evidence shows the climate has changed naturally?

Evidence for natural climate change includes ice cores (layers of ancient ice with trapped air bubbles that record past temperature and greenhouse gases), tree rings (wider in warm, wet years), pollen (showing which plants grew, and so the climate) and historical records such as harvest dates and paintings. The natural causes include orbital changes, sunspot activity and volcanic eruptions.

What is the difference between a depression and an anticyclone?

A depression is an area of low pressure with rising air, bringing cloud, rain and wind as warm and cold fronts pass; depressions cross the UK from the Atlantic and cause much of our wet, windy weather. An anticyclone is an area of high pressure with sinking air, bringing dry, calm, settled weather: hot and sunny in summer, cold and frosty or foggy in winter.

How do energy and nutrients move through an ecosystem?

Energy flows in one direction through food chains and webs, from producers (plants) to consumers, and is lost as heat at each trophic level, so food chains are short. Nutrients, by contrast, are recycled: when plants and animals die, decomposers return nutrients to the soil, where plants take them up again. Energy must be constantly replaced by sunlight, but nutrients go round and round.

Why is the tropical rainforest vulnerable to deforestation?

Most of the rainforest's nutrients are stored in the living plants, not the soil, because the warm, wet climate makes the nutrient cycle very fast. When the trees are cut down, this nutrient store is removed and the thin soil is exposed, so heavy rain quickly erodes and leaches it. Because the ecosystem is so interdependent, removing the trees can cause the whole system to collapse.

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Weather, Climate and Ecosystems (Core Theme 5): a complete overview for WJEC GCSE Geography Unit 2

A complete overview of Core Theme 5, Weather, Climate and Ecosystems, for WJEC GCSE Geography Unit 2: climate change in the Quaternary, weather patterns and processes including UK weather and tropical storms, ecosystem processes and food webs, and human activity and the sustainable management of the rainforest.

Generated by Claude Opus 4.814 min read3110-unit-2-theme-5Updated 2026-06-15

Reviewed by: AI editorial process; not yet individually human-reviewed

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What this covers
Climate change in the Quaternary
Weather patterns and processes
Ecosystems and human activity
Check your knowledge

What this covers

Core Theme 5, Weather, Climate and Ecosystems, is the first core theme of Unit 2: Environmental and Development Issues (a 1-hour 30-minute written exam, 35 percent). This overview ties together climate change in the Quaternary, weather patterns and processes (UK weather and tropical storms), ecosystem processes (food webs and nutrient cycling), and human activity and the sustainable management of the rainforest. Like Unit 1, Unit 2 is examined by data response.

Climate change in the Quaternary

The Quaternary has swung between cold glacials and warm interglacials, shown by ice cores, tree rings, pollen and historical records. Natural causes include orbital changes (Milankovitch cycles), sunspots and volcanic eruptions. Recent rapid warming is mainly human-induced, as fossil-fuel burning and deforestation raise greenhouse gases and enhance the greenhouse effect, with consequences such as sea-level rise and extreme weather.

Weather patterns and processes

Weather is day to day; climate is the long-term average. The UK's changeable weather comes from competing air masses and two systems: depressions (low pressure, cloud and rain) and anticyclones (high pressure, dry and settled). Weather hazards include UK storms and tropical storms (hurricanes), which form over warm seas (about 27 degrees Celsius) with rising moist air spinning around an eye, and are managed by prediction, protection and preparation.

Ecosystems and human activity

An ecosystem has biotic and abiotic parts. Energy flows through food chains and webs (lost as heat at each trophic level), while nutrients cycle via decomposers. Globally, ecosystems form biomes set by climate. The tropical rainforest is highly interdependent, with poor soils and a fast nutrient cycle, so deforestation (ranching, plantations, logging, mining) causes biodiversity loss, soil erosion and carbon release. It can be managed sustainably through protection, selective logging, agroforestry, ecotourism and international action.

Core Theme 5, Weather, Climate and Ecosystems, is the first core theme of WJEC Unit 2 (Environmental and Development Issues, a 1-hour 30-minute exam, 35 percent). It covers four things. First, climate change in the Quaternary: the evidence (ice cores, tree rings, pollen), natural causes (orbital changes, sunspots, volcanoes) and the recent human-induced enhancement of the greenhouse effect. Second, weather patterns and processes: weather versus climate, air masses, depressions and anticyclones that shape UK weather, and weather hazards including UK storms and tropical storms. Third, processes and interactions within ecosystems: biotic and abiotic components, energy flow through food chains and webs (lost at each trophic level), nutrient cycling by decomposers, and the global pattern of biomes. Fourth, human activity and ecosystems: the interdependence and poor soils of the tropical rainforest, the causes and impacts of deforestation, and strategies for sustainable management. The whole theme is examined by data response.

Check your knowledge

Name two sources of evidence for past climate change. (2 marks)
Give two natural causes of climate change. (2 marks)
What is the difference between weather and climate? (2 marks)
Contrast a depression and an anticyclone. (4 marks)
What conditions does a tropical storm need to form? (3 marks)
How is energy lost along a food chain? (2 marks)
Why are rainforest soils poor? (2 marks)
Give two strategies for managing a rainforest sustainably. (2 marks)

Solutions

Q1: Any two: ice cores, tree rings, pollen, historical records.
Q2: Any two: orbital changes (Milankovitch cycles), sunspot activity, volcanic eruptions.
Q3: Weather is the day-to-day state of the atmosphere; climate is the average weather over about 30 years.
Q4: Depression: low pressure, rising air, cloud, rain and wind. Anticyclone: high pressure, sinking air, dry, calm, settled weather (hot in summer, cold/foggy in winter).
Q5: Warm ocean water (about 27 degrees Celsius), rising warm, moist air that condenses and releases heat, and the Coriolis effect to make it spin.
Q6: Energy is lost as heat (through respiration, movement and waste) at each trophic level, so less passes to the next.
Q7: Most nutrients are stored in the living plants, not the soil, and the fast nutrient cycle means dead material is quickly recycled.
Q8: Any two: national parks/protection, selective logging and replanting, agroforestry, ecotourism, international agreements/debt-for-nature swaps.

Sources & how we know this

WJEC GCSE Geography (Wales) specification (3110) — WJEC (2019)